长距离重力流输水系统的爆管过渡过程和阀门关闭规律的研究

Research on the Pipe Burst Transient Progress and Valve Closure Law of Long-distance and Gravity Flow Water Supply System

由于爆管事故具有随机性、不可预知性,在长距离重力流输水系统中一般无法通过非破坏性试验直接测量爆管时的压力和流量变化过程。根据瞬变流理论,在输水管道的水锤基本方程上,引入爆管边界,建立爆管的水力学模型,并采用特征线法求解。通过假设在输水工程管线不同位置处发生爆管,比较不关阀和关阀两种条件下爆管后管线内的压力瞬变过程和爆管点漏损量的变化,结果表明通过合理选取爆管点上下游液控阀的关闭规律,能够明显减小爆管泄漏量,避免爆管后关阀操作不当可能诱发的二次水锤及次生危害。

Because of the randomness and unpredictability of the pipe burst accident, it is generally impossible to directly measure the pressure and flow change process in the long-distance gravity flow water transmission system through the non-destructive test.According to the transient flow theory, the boundary of the pipe burst is incorporated into basic equation of water hammer in pipelines, the hydraulics model of pipe burst is established, and the characteristic line method is applied to solve it.By assuming that the pipe burst occurs at different locations of the pipeline, the pressure transient process and the leakage of the explosion pipe point in the pipeline and the results show that the leakage can be reduced obviously by selecting the appropriate closing law of the upstream and downstream valve of the burst point reasonably.Therefore it also avoids the second water hammer and secondary damage that may be induced by the improper operation of the shutdown valve.